SAD -- Seasonal Affective Disorder
The DSM-IV classifies seasonal affective disorder (SAD) as a mood disorder with a seasonal pattern. People afflicted with SAD may notice that they become depressed in the winter months, usually between September and April, when days are shorter and there are fewer hours of sunlight. It is estimated that roughly 10% of individuals afflicted with mood disorders may suffer from SAD.
SAD is characterized by the following symptoms:
- sleep disturbance -- usually oversleeping
- lethargy -- feelings of fatigue and lack of motivation
- overeating or weight gain -- cravings for carbohydrates, especially sweets
- depression -- apathy, guilt, reduced self-esteem, sadness
- social withdrawal -- irritability and desire to be alone
- anxiety -- tension and decreased ability to deal with stress
- loss of libido -- decreased interest in sex
- mood changes -- overactivity in spring and autumn experienced by some sufferers
Although the exact mechanism is unknown, lack of exposure to adequate sunlight and imbalances of two key neurotransmitters -- serotonin and melatonin -- may be implicated in triggering this type of depression. Genetic predisposition and stress also may play a role in the etiology of SAD according to Dr. Norman Rosenthal, the physician who first described seasonal patterns of depression. Treatments for SAD include phototherapy and antidepressant medication. Sufferers may notice a decrease in their symptoms by adopting healthy eating habits and adhering to a regular sleep schedule. Exercising outside may prove especially helpful for two reasons -- release of endorphins and increased exposure to sunlight.
Phototherapy involves exposure to full spectrum lighting for one to two hours per day, usually in the morning. Light boxes and visors provide this kind of exposure. Alternatively, dawn simulators initially provide low levels of light and increase the levels throughout the morning -- mimicking light exposure experienced in the early morning hours as the sun rises. Therapeutic levels of light are measured in a unit of illumination termed, the lux. The minimum effective dose for treating SAD is around 2,500 lux although some studies suggest certain patients may achieve beneficial effects from as little as 100 lux. Antidepressant medications such as sertraline (Zoloft®), paroxetine (Paxil®), citalopram (Celexa) and fluoxetine (Prozac®) may be effective in alleviating the symptoms of SAD and are often times used in conjunction with light therapy. Some vendors of light boxes, dawn simulators, and light visors include:
Apollo Light Systems
http://www.apollolight.comBio-Light from Enviro-Med
http://www.bio-light.comSun Box Co.
http://www.sunboxco.comOutside In
http://www.outsidein.co.uk
The great majority of people afflicted with SAD achieve relief from either one or a combination of the therapies outlined above.
